In terms of dietary health, there is a saying in traditional Chinese medicine that during the summer solstice, the heart fire is dominant. If the heart fire is too strong, it can suppress the metal element of the lungs (based on the theory of the Five Elements). Therefore, the "Essentials from the Golden Cabinet" has a saying of "do not consume foods that stimulate the heart" during the summer. According to the relationships between the Five Elements (fire for summer), the Five Seasons (long for summer), the Five Organs (heart), and the Five Tastes (bitter is recommended), bitter foods can also help nourish the heart qi and regulate the lung qi.
During the summer solstice, it is a season of sweating. Excessive sweating leads to the loss of salt. If the heart muscle lacks salt, irregular heartbeat may occur. Traditional Chinese medicine believes that during this time, it is advisable to consume more sour foods to stabilize the exterior of the body, and consume more salty foods to nourish the heart. In "Plain Questions · Discussion on the Methods of Treating Diseases According to the Seasons", it is stated that the heart governs summer, and when the heart is weak, it should be immediately treated with sour foods. When the heart desires to be relaxed, it should be immediately treated with salty foods. By using salty foods to nourish it, the sweet taste can be used to purge it. This means that the qi storage is soft, so salt is used to soften it.
From the perspective of yin and yang theory, during the summer month, yin is hidden internally, so the diet should not be too cold. As stated in "Collection for Nourishing the Body", "During the summer season, the heart is strong but the kidneys are weak. Even though it is very hot, it is not advisable to eat cold foods such as ice, honey water, cold jelly, and cold porridge. Being full and exposed to cold will lead to sudden collapse." When the heart is strong but the kidneys are weak, it means that there is external heat and internal cold. Therefore, cold foods should not be consumed in large quantities. It is acceptable in moderation, but excessive consumption will damage the spleen and stomach, leading to vomiting and diarrhea. Watermelon, mung bean soup, and plum red bean soup are excellent for relieving thirst and heat, but they should not be consumed ice-cold.
According to the relationships between the organs in traditional Chinese medicine, it is said that "if the kidneys lack the heart fire, the water will be cold; if the heart lacks the kidney water, the fire will be intense. The heart must receive the nourishment of kidney water, and the kidneys must receive the warmth of heart fire." From this, we can see the importance of the relationship between the heart and kidneys.
During the summer, the climate is hot, and the digestive function of the body is relatively weak. Therefore, the diet should be light and not excessively fatty or sweet. It is advisable to consume more whole grains to cool down the body. Avoid consuming hot foods to prevent overheating. It is important to consume melons and fruits in moderation to avoid damaging the spleen and stomach. Foods that are thick and greasy should be consumed in small quantities to prevent heat generation and the development of boils.
